The invention relates to a heating system for supplying thermal energy to a heater of a machine in which a working medium performs a thermodynamic cycle, for example, a hot-gas engine. The system comprises a metal, a metal alloy, a metal salt or a mixture of metal salts serving as a heat-transporting medium and being present in a closed space, and to which on the one hand thermal energy can be supplied from a heat source through a wall, with the transporting medium changing from the liquid phase into the vapour phase, and on the other hand can deliver the absorbed thermal energy to the heater with the transporting medium changing from the vapour phase into the liquid phase.
A heating system of the above-described type is known from Dutch patent specification 58,355. Such a system in which the heat of evaporation and condensation is used to transport thermal energy from the heat source to the heater for example, has the advantage that a large heat transport can be obtained without complicated and expensive pumps or valves being necessary for transport. The transporting medium is chosen to be so as to have a condensation temperature which corresponds to the operating temperature of the heater of the thermo-dynamic machine. The transporting medium is then evaporated by the thermal energy supplied from the heat source. As a result of the fact that the temperature and hence the vapour pressure at the area of the heat source is slightly higher than at the area of the heater, the vapour will flow to the heater. The vapour condenses there while supplying thermal energy and the condensate can be conducted back again to the heat source either by gravity or by means of a simple pump.